Relation to Altitude Adaptation and Antioxidant Defence System in Five Shrubs and Trees Species From Middle Taurus Mountains

Abstract

Changes of antioxidative defence systems were investigated as depend on altitude in the leaves of five shrubs and trees species
from Middle Taurus Mountains. Leaves of angiosperm species Quercus coccifera, Styrax officinalis, Pistacia terebinthus, Rosa
canina, and a gymnosperm species Juniperus excelsa collected from different sites between 400-1500 m. Leaf water contents
were lower at high altitudes in all species, except J. excelsa. The contents of chlorophyll a and b increased in leaves of angiosperm
species but decrease in leaves of gymnosperm, J.excelsa, from high altitude. Total ascorbate contents decreased in S. officinalis
and R. canina from high altitude, but increased in the other species. α-Tocopherol contents were higher in all of the samples from
high altitude. Superoxide dismutase (SOD), especially Mn-SOD activities were increased in samples from higer altitude except for
R. canina. Glutathione reductase (GR) activities were increased in leaves of Q. coccifera, S. officinalis and R. canina from high
altitude. These results suggested that angiosperm and gymnosperm species can give different biochemical responses to oxidative
stress increasing depend on altitude. The higher levels of antioxidant compounds and antioxidant enzyme activities required for
adaptation to high altitudes of angiosperm species.